copy-to-clipboard for UserName Value

[kreisel]

there is no copy-to-clipboard-button for UserName Value. You have to click on the UserName Value to mark and strg+c to copy it

[Nam Nguyen]

Issue #53 was marked as a duplicate of this issue.

[Nam Nguyen]

Fix #45: Make all non-blob fields copyable.

Apparently, clicking on and Ctrl-C'ing a field is too much.

→ <<cset 6793c775326f>>